RFC: Demangle partial symbols and save memory too

[Andrew Cagney]

> Personally, I'd prefer that name be const char *.  And, for that
>> matter, I'd rather have the demangled name member of struct
>> general_symbol_info be a const char *: it will be shared, so changing
>> it really would be bad.  But that's really a separate issue; I'll
>> submit a patch for that one myself later.
> 
> 
> Thanks for reminding me; I'll fix the first const char *.  You'll
> notice I fixed the ugly places I was modifying it already, from our
> last discussion.

Yes please!  The more `char *' -> `const char *' stomping, the better.

Andrew